diff options
author | Joerg Mueller <nexyon@gmail.com> | 2012-12-10 20:58:47 +0400 |
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committer | Joerg Mueller <nexyon@gmail.com> | 2012-12-10 20:58:47 +0400 |
commit | 245345fba5f44b5c8562c826ca0053fa5bbd2ff3 (patch) | |
tree | fb7c6b8eaac7916b387e929f972da150f8ac6d39 /intern/audaspace/FX/AUD_LowpassCalculator.cpp | |
parent | e1100cb65565d2218272222fba708da14bc48d94 (diff) |
Audaspace:
Implemented forgotten Calculator classes from boost migration.
Diffstat (limited to 'intern/audaspace/FX/AUD_LowpassCalculator.cpp')
-rw-r--r-- | intern/audaspace/FX/AUD_LowpassCalculator.cpp | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/intern/audaspace/FX/AUD_LowpassCalculator.cpp b/intern/audaspace/FX/AUD_LowpassCalculator.cpp new file mode 100644 index 00000000000..57452f09038 --- /dev/null +++ b/intern/audaspace/FX/AUD_LowpassCalculator.cpp @@ -0,0 +1,27 @@ +#include "AUD_LowpassCalculator.h" + +#include <cmath> + +#ifndef M_PI +#define M_PI 3.14159265358979323846 +#endif + +AUD_LowpassCalculator::AUD_LowpassCalculator(float frequency, float Q) : + m_frequency(frequency), + m_Q(Q) +{ +} + +void AUD_LowpassCalculator::recalculateCoefficients(AUD_SampleRate rate, std::vector<float> &b, std::vector<float> &a) +{ + float w0 = 2 * M_PI * m_frequency / rate; + float alpha = sin(w0) / (2 * m_Q); + float norm = 1 + alpha; + float c = cos(w0); + a.push_back(1); + a.push_back(-2 * c / norm); + a.push_back((1 - alpha) / norm); + b.push_back((1 - c) / (2 * norm)); + b.push_back((1 - c) / norm); + b.push_back(b[0]); +} |